Change #1123494 had a related patch set uploaded (by Cmelo; author: Cmelo):

[mediawiki/extensions/GrowthExperiments@master] POC for Collaboration List module on the Newcomer Homepage

https://gerrit.wikimedia.org/r/1123494

Test wiki created on Patch demo by CMelo (WMF) using patch(es) linked to this task:
http://patchdemo.wmcloud.org/wikis/b67ea86a3c/w/

Test wiki on Patch demo by CMelo (WMF) using patch(es) linked to this task was deleted:

http://patchdemo.wmcloud.org/wikis/b67ea86a3c/w/

Test wiki created on Patch demo by CMelo (WMF) using patch(es) linked to this task:
http://patchdemo.wmcloud.org/wikis/67f47043b9/w/

Test wiki on Patch demo by CMelo (WMF) using patch(es) linked to this task was deleted:

http://patchdemo.wmcloud.org/wikis/67f47043b9/w/

Hi there @ifried, @VPuffetMichel , @Daimona, @MHorsey-WMF, here is the result of my one-day investigation on this.

I was able to create a POC and demo it today to the team on the demo/retro but here is an image of the "final result" of what I tried, it is a list of events that users could filter by.
All the events data are fake and the filter don't do anything it is just to show what I had in mind and what I understood from the AC of this task.

Testing Instructions

In order to test this you need to use this patch:
https://gerrit.wikimedia.org/r/c/mediawiki/extensions/GrowthExperiments/+/1123494

Installation

Install the GrowthExperiments extension and add it to your LocalSettings.php:

php
wfLoadExtension( 'GrowthExperiments' );
$wgGEHomepageEnabled = true;
$wgGENewcomerTasksEnabled = true;
$wgGEHelpPanelEnabled = true;

It uses VisualEditor, so add it too:

wfLoadExtension( 'VisualEditor' );
$wgDefaultUserOptions['visualeditor-enable'] = 1;
$wgHiddenPrefs[] = 'visualeditor-enable';
$wgVirtualRestConfig['modules']['parsoid'] = [
    'url' => 'http://localhost:8142',  // Ensure Parsoid runs at this port
    'domain' => 'localhost',
    'prefix' => 'localhost'
];

Configuration

Go to Special:Preferences
Check Display newcomer homepage under Newcomer editor features
Then check the page on Special:Homepage

Next Steps

It sounds doable to implement something like this demo.
To do this, we will need an API to get the list of events and filter it.

One last thing: I just did a PoC of what I understood from the task. We may need other things depending on the final scope of this new feature.

BTW I tried to create a patch demo but it fails, with the error below:

[c32ef30ae65ba2673fb307e4] /wikis/67f47043b9/wiki/Special:Homepage Error: Class "CirrusSearch\CirrusSearchServices" not found

Backtrace:

from /var/www/html/wikis/67f47043b9/w/extensions/GrowthExperiments/ServiceWiring.php(125)
#0 /var/www/html/wikis/67f47043b9/w/vendor/wikimedia/services/src/ServiceContainer.php(440): Wikimedia\Services\ServiceContainer::{closure}()

Last note: I will be OOO until Wednesday it is Brazilian Carnival holidays, I will be back on Wednesday Afternoon Brazilian Time.

In T386958#10589585, @cmelo wrote:

Hi there @ifried, @VPuffetMichel , @Daimona, @MHorsey-WMF, here is the result of my one-day investigation on this.

Thank you for exploring this.

It sounds doable to implement something like this demo.
To do this, we will need an API to get the list of events and filter it.

I'm curious about where this code will leave eventually. Does GrowthExperiments provide a hook to let other extensions add more modules? I think I would prefer this code to be in CampaignEvents, because we'd be maintaining it, and we could use the existing abstractions, including any of our internals, to list the events.

BTW I tried to create a patch demo but it fails, with the error below:

[c32ef30ae65ba2673fb307e4] /wikis/67f47043b9/wiki/Special:Homepage Error: Class "CirrusSearch\CirrusSearchServices" not found

Sadly, the master version of GrowthExperiments has an unexpected hard dependency on CirrusSearch. It's not only patch demo, it also breaks all load.php requests locally if you don't have CirrusSearch installed. This is tracked in T386690. The easy workaround is to just enable CirrusSearch (you don't really need to configure it or make it work, as long as it's there). I also just found an unexpected hard dependency on EventLogging, filed as T387544.

Blocked due to design investigation in progress